Search

Abstract The Ogasawara Islands, one of the UNESCO World Natural Heritage Site located about 1000 km south of Japan’s main island, harbor numerous endemic species, many of which are as endangered. One of the endemic plant species, Lobelia boninensis, found in the Mukojima, Chichijima, and Hahajima archipelagoes, is endangered due to predation. As part of conservation efforts, translocation is now underway, especially on Chichijima. However, we lack essential information, such as the genetic population structure, to develop appropriate translocation strategies for both wild and planted individuals. Here, we aimed to identify the conservation units and the origin of planted individuals by estimating the genetic population structure and phylogenetic relationships across all habitats of this species. We identified two distinct genetic clusters, indicating genetic differentiation between the northern and southern populations. The genetic population components detected at an isolated site on Chichijima showed a mixture of these distinct clusters, probably due to hybridization. The transplanted individuals in Chichijima were found to have originated from a population in Hahajima. These results suggest the presence of two distinct conservation units. Furthermore, the current translocation strategy poses a risk of genetic contamination between these units, highlighting the need for revised conservation management practices.

ABSTRACT The genus Camellia is widely distributed, primarily in East Asia. Camellia japonica is located at the northern limit of this genus distribution, and understanding changes in its distribution is crucial for understanding the evolution of plants in this region, as well as their relationship with geological history and climate change. Moreover, the classification of sect. Camellia in Japan has not been clarified. Therefore, this study aims to understand the evolutionary history of the Japanese sect. Camellia. The genetic population structure was analysed using SNP data and MIG‐seq. The relationship between the Japanese sect. Camellia, including the related species in China, was further inferred from the phylogeny generated by RA x ML, SplitsTree and PCA. Population genetic structure was inferred using a Bayesian clustering method (ADMIXTURE). We subsequently employed approximate Bayesian computation, which was further supported by the coalescent simulations (DIYABC, fastsimcoal and Bayesian Skyline Plots) to explore the changes in population, determining which events appropriately explain the phylogeographical signature. Ecological niche modelling was combined with genetic analyses to compare current and past distributions. The analyses consistently showed that C. japonica and C. rusticana are distinct, having diverged from each other during the Middle to Late Miocene period. Furthermore, C. japonica differentiated into four major populations (North, South, Ryukyu‐Taiwan and Continent). The Japanese sect. Camellia underwent speciation during archipelago formation, reflecting its ancient evolutionary history compared with other native Japanese plants. C. rusticana did not diverge from C. japonica in snow‐rich environments during the Quaternary period. Our results suggest that both species have been independent since ancient times and that ancestral populations of C. japonica have persisted in northern regions. Furthermore, the C. japonica population on the continent is hypothesised to have experienced a reverse‐colonisation event from southern Japan during the late Pleistocene glaciation.

Abstract Anthropogenic activities have reduced ecotones between the ocean and land, which is likely to threaten the population of brackish‐water brachyuran crabs. To assess the current status of these crabs, we examine the population genetic structures of three semi‐terrestrial brachyuran crabs widely distributed along the coast of the Japan and to clarify factors determining their genetic structures. We collected 184 Orisarma dehaani, 252 Chiromantes haematocheir, and 151 Helice tridens crabs from 36 localities of the Japanese archipelago. Genome‐wide SNP data from these crabs were analyzed using MIG‐seq. Bayesian clustering of STRUCTURE and DAPC analysis were used to identify genetically disturbed populations and to visualize genetic differentiation between local populations. Genetic population structure showed clear differentiation between populations on the Pacific coast of the Tohoku region and on other Japanese coasts in O. dehaani, but not in C. haematocheir or H. tridens. The inbreeding coefficient of O. dehaani was significantly higher on the Pacific coast of the Tohoku region compared to other Japanese coasts. C. haematocheir and H. tridens had homogeneous genetic structures along the Japanese coast, but showed genetic differentiation of a local population at their range limits. Thus, O. dehaani showed little gene flow and clear genetic differentiation between populations in the Tohoku Pacific region and those on other Japanese coasts due to ocean currents. Although such a regional differentiation was not found in C. haematocheir and H. tridens, one population of C. haematocheir was genetically isolated at the edge of its distribution range and likely vulnerable to environmental changes.

Japan has 16 native species of the genus Hosta Tratt. (Asparagaceae). A recent study on Hosta based on field surveys and molecular phylogenetic analyses resulted in the discovery of six unknown taxa in Kochi Prefecture, Shikoku Island, southwestern Japan. We aimed to identify these unknown taxa. Therefore, we constructed a finely resolved phylogeny for 320 Hosta samples collected from the Honshu, Shikoku, and Kyushu Islands using multiplex inter-simple sequence repeat genotyping by sequencing (MIG-seq). Based on this phylogenetic analysis and related morphological observations, we describe five new species, H. longipedicellata sp. nov., H. minazukiflora sp. nov., H. polyneuronoides sp. nov., H. samukazemontana sp. nov., and H. takiminazukiflora sp. nov. and one new subspecies, H. takiminazukiflora subsp. grandis subsp. nov. In addition, we propose two new status assignments, H. tardiva subsp. densinervia comb. and stat. nov. and H. scabrinervia stat. nov. We also propose classifying H. kikutii var. tosana as a species, H. tosana. Further studies that combine MIG-seq with careful morphological observations are needed for Hosta plants on all Japanese islands, which may result in the discovery of even more undescribed species.

Species delimitation within the genus Goodyera is challenging among closely related species, because of phenotypic plasticity, ecological variation, and hybridization that confound identification methods based solely on morphology. In this study, we investigated the identity of Goodyera crassifolia H.-J.Suh, S.-W.Seo, S.-H.Oh & T.Yukawa, morphologically similar to Goodyera schlechtendaliana Rchb.f. This recently described taxon has long been known in Japan as “Oh-miyama-uzura” or “Gakunan” and considered a natural hybrid of G. schlechtendaliana and G. similis Blume (= G. velutina Maxim. ex Regel). Because the natural hybrid between G. schlechtendaliana and G. similis was described as G. × tamnaensis N.S.Lee, K.S.Lee, S.H.Yeau & C.S.Lee before the description of G. crassifolia, the latter might be a synonym of G. × tamnaensis. Consequently, we investigated species boundaries and evolutionary history of G. crassifolia and its closely related taxa based on multifaceted evidence. Consequently, morphological examination enabled us to distinguish G. crassifolia from other closely related species owing to the following characteristics: coriaceous leaf texture, laxly flowered inflorescence, long pedicellate ovary, large and weakly opened flowers, and column with lateral appendages. Ecological investigation indicates that G. crassifolia (2n = 60) is agamospermous, requiring neither pollinators nor autonomous self-pollination for fruit set, whereas G. schlechtendaliana (2n = 30) is neither autogamous nor agamospermous but is obligately pollinator-dependent. MIG-seq-based phylogenetic analysis provided no evidence of recent hybridization between G. crassifolia and its close congeners. Thus, molecular phylogeny reconstructed from MIG-seq data together with morphological, cytological, and ecological analyses support the separation of G. crassifolia as an independent species.

Hydrangea marunoi Tagane & S. Fujii, from the Kimotsuki Mountains in the Ohsumi Peninsula, southern Japan, is described and illustrated. It is morphologically similar to H. alternifolia in having three-petaloid calyx lobes in marginal flowers, but is distinguished by the larger stamen number, and longer styles and seeds. Multiplex ISSR genotyping by sequencing (MIG-seq) demonstrated that the new species is monophyletic and closely related to H. amamiohsimensis and H. moellendorffii rather than H. alternifolia.

Contrasting theories exist regarding how Norway spruce recolonized Fennoscandia after the last glaciation. Here, the authors provide evidences from sedimentary ancient DNA and modern population genomics to support that Norway spruce was present in southern Fennoscandia shortly after deglaciation and the early Holocene migration from the east.

According to the contemporary classification of Hydrangea native to Japan, H. serrata is a polymorphic species including six varieties. We discovered a plant identified as H. serrata, but morphologically distinct from previously known varieties, in Yakushima island where approximately 50 endemic species are known. To determine the relationship of this plant with previously known varieties, we examined morphology and constructed a highly resolved phylogeny of H. serrata and its relatives using three chloroplast genomic regions, rbcL, trnL intron, psbA-trnH, and two nuclear genomic regions, ITS1 and ITS2, and Multiplex ISSR genotyping by sequencing (MIG-seq). Based on these morphological and phylogenetic observations, we describe Hydrangea acuminata subsp. yakushimensis subsp. nov. as a newly discovered lineage in Yakushima, Japan and propose Hydrangea minamitanii stat. nov. and Hydrangea acuminata subsp. australis stat. nov. which were previously treated as varieties of H. serrata.

An unknown taxon of Stellaria was discovered in Yakushima, a Japanese island known to harbor several endemic species. To determine the identity of this taxon, this study employed MIG-seq for the reconstruction of a finely resolved phylogenetic tree of the newly discovered taxon, along with some related species of Stellaria. The results showed that the newly discovered taxon is a relative of S. alsine. Based on this result, Stellaria alsine subsp. nana subsp. nov. was published.

Molecular phylogenetic studies of Hosta pulchella (Asparagaceae) and its relatives, which are native to Japan, have been conducted and resulted in a highly resolved phylogeny. Specifically, the relationship of H. pulchella to H. alata Hatusima, nom. nud. is investigated. These data include genome-wide SNPs obtained through conducting multiplexed ISSR genotyping by sequencing (MIG-seq). Based on these phylogenetic results, morphological observations, distribution, and differences in flowering periods of H. alata collections sympatric with H. pulchella, we find the two species closely related, but distinct. As such, we formally describe Hosta alata sp. nov. from the Oita Prefecture of Kyushu island, southwestern Japan.

Anthropogenic activities, such as the movement of plants through greening, can result in genetic disturbance that can interfere with local adaptation in wild populations. Although research is underway to prevent genetic disturbance associated with greening, genetic disturbance of intraspecific polyploidy, which is estimated to be present in 24% of vascular plants, has not been well studied. Liriope muscari is a polyploid complex with known diploid (2n = 36), tetraploid (2n = 72), and hexaploid (2n = 108) forms. The plants of this species tolerate dry and hot conditions and are therefore frequently used for greening and gardening. However, the distribution of this polyploid in Japan, its genetic structure, and genetic disturbance are not known. In this study, we investigated the polyploidy distribution and genetic structure in naturally distributed L. muscari in Japan using chloroplast DNA (cpDNA) haplotypes and nuclear DNA (nDNA). Commercially produced individuals were also studied and compared with natural populations to assess any genetic disturbance of the ploidy complex in this species. Chromosome counts, cpDNA, and nDNA results showed three genetically and cytologically distinct groups in Japan: first, a tetraploid group in mainland Japan; second, a hexaploid group in the Ryukyu Islands; and third, a diploid and tetraploid group in the Ryukyu Islands. Significant isolation by distance was also detected within the three groups (p = 0.001). Genetic disturbance due to greening and gardening should be avoided among the three groups. Genetic disturbance can be reduced by using individuals derived from natural populations that are close to the sites used for greening and gardening. For commercially produced individuals, genetic disturbance is unlikely in the Kanto region, an area of high usage, while genetic disturbance is thought possible in the Ryukyu Islands.

Several individuals of an unidentified Goodyera taxon were discovered in Tomakomai City, Hokkaido Prefecture, Japan. Detailed morphological analysis suggests that this taxon is a natural hybrid between Goodyera schlechtendaliana and Goodyera henryi, based on characteristics such as leaf margins, texture, venation patterns, rachis length, hair morphology on the ovary, and the shapes of the lip apex and rostellum. Supporting this, molecular data from genome-wide markers using next-generation sequencing (MIG-seq data) indicate that G. xkazumae is a hybrid between G. schlechtendaliana and G. henryi. Neighbor-Net phylogenetic analysis shows G. xkazumae occupies an intermediate position between the putative parent species. STRUCTURE analysis further confirms that G. xkazumae comprises genetic components from both species. Therefore, we conclude that this taxon is a natural hybrid based on comprehensive morphological and molecular evidence. [ABSTRACT FROM AUTHOR]

Abstract A new type of cold/ultracold neutron detector that can realize a spatial resolution of less than 100 nm was developed using nuclear emulsion. The detector consists of a fine-grained nuclear emulsion coating and a 50-nm thick $$^{10}\hbox {B}_4 \hbox {C}$$ 10B4C layer for the neutron conversion. The detector was exposed to cold and ultracold neutrons (UCNs) at the J-PARC. Detection efficiencies were measured as (0.163 ± 0.015 (stat) ± 0.013 (sys))% and (10.3 ± 1.3 (stat) ± 1.1 (sys))% for cold and ultracold neutrons consistently with the $$^{10}$$ 10 B content in the converter. Positions of individual neutrons can be determined by observing secondary particle tracks recorded in the nuclear emulsion. The spatial resolution of incident neutrons were found to be in the range of 11–99 nm in the angle region of tan$$\theta \le 1.9$$ θ≤1.9 , where $$\theta $$ θ is the angle between a recorded track and the normal direction of the converter layer. The achieved spatial resolution corresponds to the improvement of one or two orders of magnitude compared with conventional techniques and it is comparable with the wavelength of UCNs.

This study discusses how much of the biases in top-of-atmosphere (TOA) radiation and clouds can be removed by parameter tuning in the present-day simulation of a climate model in the Coupled Model Inter-comparison Project phase 5 (CMIP5) generation. We used output of a perturbed parameter ensemble (PPE) experiment conducted with an atmosphere–ocean general circulation model (AOGCM) without flux adjustment. The Model for Interdisciplinary Research on Climate version 5 (MIROC5) was used for the PPE experiment. Output of the PPE was compared with satellite observation data to evaluate the model biases and the parametric uncertainty of the biases with respect to TOA radiation and clouds. The results indicate that removing or changing the sign of the biases by parameter tuning alone is difficult. In particular, the cooling bias of the shortwave cloud radiative effect at low latitudes could not be removed, neither in the zonal mean nor at each latitude–longitude grid point. The bias was related to the overestimation of both cloud amount and cloud optical thickness, which could not be removed by the parameter tuning either. However, they could be alleviated by tuning parameters such as the maximum cumulus updraft velocity at the cloud base. On the other hand, the bias of the shortwave cloud radiative effect in the Arctic was sensitive to parameter tuning. It could be removed by tuning such parameters as albedo of ice and snow both in the zonal mean and at each grid point. The obtained results illustrate the benefit of PPE experiments which provide useful information regarding effectiveness and limitations of parameter tuning. Implementing a shallow convection parameterization is suggested as a potential measure to alleviate the biases in radiation and clouds.

Fabrication of fine TiN particle-dispersed dense Al2O3 composites with the compositions of Al2O3/TiN=100/0~90/10 vol% has been conducted from Al2O3/(Ti,TiN0.3) mixed powder compacts by capsule-free hot isostatic pressing (HIP) utilizing high-pressure N2 SHS. Fine Ti powders (φ ~ 0.3 μm) with TiN0.3 phase were prepared by thermal decomposition of planetary ball-milled fine TiH2 powders at 400 °C (673 K) for 1 h in a vacuum, followed by heating in N2 at 200°C (473 K) for 2 h. The Al2O3 powder compacts (relative densities of 57.2-57.8%) with homogeneously dispersed (Ti,TiN0.3) particles were prepared. The mixed powder compacts were hot isostatically pressed (HIPed) under the conditions of 1350 °C (1623 K) at 7 MPa N2 for 1 h, followed by the heating at the same temperature for 2 h under 196 MPa-N2. At the first stage of heating [1350°C (1623K)/7MPa/1h], solid/gas reaction of SHS between (Ti,TiN0.3) and N2 was introduced to form TiN and densification of the Al2O3 powder compacts up to the relative density of 92-93% with closed pores was performed. And at the sequent second stage [1350 °C (1623K)/196MPa/2h], densification of the most of pre-sintered composites consisting of Al2O3 and TiN reached higher relative densities than 98.5%. Dispersion of TiN particles (~φ 0.30 μm) in the composites suppressed the grain growth of Al2O3 during HIP-sintering. Mechanical properties, such as bending strength (σb), Vickers hardness (HV), fracture toughness (K1C), and electrical resistivity (ρ) of the composites were evaluated as a function of TiN content; the maximum values of σb=640 MPa, HV=19.5 GPa, and KIC=4.5 MPa・m1/2 were obtained in the Al2O3/TiN=97/3~95/5 vol% composites. Among the composites, the lowest ρ value of 2.6×103 Ω・m was attained at Al2O3/TiN=90/10 vol% composite.

As reações liquenoides por drogas são mais comuns na pele, mas também podem ocorrer na mucosa bucal. Estas lesões são de difícil diagnóstico por causa de sua semelhança clínica com às do líquen plano oral idiopático. O presente artigo relata um caso de reação liquenoide em mucosa bucal, associado ao uso de carbamazepina, no qual o processo de diagnóstico é enfatizadoLichenoid drug reactions are more commom in skin, but they may also occur in the oral mucosa. It is difficult to diagnose these lesions due to their clinical similarity to the idiopathic oral lichen planus lesions. The present article reports a case of lichenoid reaction in oral mucosa associated to the use of carbamazepine, emphasizing the diagnostic process

O carcinoma epidermóide constitui a neoplasia maligna mais comum da boca, afetando principalmente indivíduos com mais de 50 anos. Sua ocorrência em jovens, com idade inferior a 40 anos, é rara (1 a 6% dos casos). Descreve-se um caso de carcinoma epidermóide acometendo dorso e borda da língua, classificado como T2N1M0 (estádio III), em paciente do sexo feminino, leucoderma, 25 anos, não-fumante e não-etilista. A apresentação inicial do caso era de ulceração profunda com dor intensa. Fatores predisponentes locais e gerais, diagnóstico diferencial e prognóstico são discutidos, bem como a revisão da literatura referente a diversos aspectos do carcinoma epidermóide em jovens.Squamous cell carcinoma is the most common malignant neoplasm of the oral cavity, usually affecting individuals over 50 years of age. It rarely occurs in patients who are less than 40 years old (1 to 6%). This report describes a case of squamous cell carcinoma, staged T2N1M0 (stage III), involving the lateral border and dorsal surface of the tongue of a 25-year-old white female patient, with no smoking or drinking habits. Initial tumor presentation was of deep ulceration and intense pain. This report focuses on the etiological factors, differential diagnosis and prognosis related to the case. Additionally, a brief literature review regarding squamous cell carcinoma in young patients is also included.

To trace the fate of individual pollen grains through pollination processes, we determined genotypes of single pollen grains deposited on Hemerocallis stigmas in an experimental mixed-species array. Hemerocallis fulva, pollinated by butterflies, has diurnal, reddish and unscented flowers, and H. citrina, pollinated by hawkmoths, has nocturnal, yellowish and sweet scent flowers. We observed pollinator visits to an experimental array of 24 H. fulva and 12 F2 hybrids between the two species (H. fulva and H. citrina) and collected stigmas after every trip bout of swallowtail butterflies or hawkmoths. We then measured selection by swallowtail butterflies or hawkmoths through male and female components of pollination success as determined by single pollen genotyping. As expected, swallowtail butterflies imposed selection on reddish color and weak scent: the number of outcross pollen grains acquired is a quadratic function of flower color with the maximum at reddish color, and the combined pollination success was maximal at weak scent (almost unrecognizable for human). This explains why H. fulva, with reddish flowers and no recognizable scent, is mainly pollinated by swallowtail butterflies. However, we found no evidence of hawkmoths-mediated selection on flower color or scent. Our findings do not support a hypothesis that yellow flower color and strong scent intensity, the distinctive floral characteristics of H. citrina, having evolved in adaptations to hawkmoths. We suggest that the key trait that triggers the evolution of nocturnal flowers is flowering time rather than flower color and scent.

The daylily (Hemerocallis fulva) and nightlily (H. citrina) are typical examples of a butterfly-pollination system and a hawkmoth-pollination system, respectively. H. fulva has diurnal, reddish or orange-colored flowers and is mainly pollinated by diurnal swallowtail butterflies. H. citrina has nocturnal, yellowish flowers with a sweet fragrance and is pollinated by nocturnal hawkmoths. We evaluated the relative roles of flower color and scent on the evolutionary shift from a diurnally flowering ancestor to H. citrina. We conducted a series of experiments that mimic situations in which mutants differing in either flower color, floral scent or both appeared in a diurnally flowering population. An experimental array of 6 × 6 potted plants, mixed with 24 plants of H. fulva and 12 plants of either F1 or F2 hybrids, were placed in the field, and visitations of swallowtail butterflies and nocturnal hawkmoths were recorded with camcorders. Swallowtail butterflies preferentially visited reddish or orange-colored flowers and hawkmoths preferentially visited yellowish flowers. Neither swallowtail butterflies nor nocturnal hawkmoths showed significant preferences for overall scent emission. Our results suggest that mutations in flower color would be more relevant to the adaptive shift from a diurnally flowering ancestor to H. citrina than that in floral scent.

A decomposition problem of max–min type for a fuzzy relation is proposed. A fast method is derived by transforming slightly the derivatives in the traditional gradient algorithm and by updating simultaneously the prototype relation. The complexities of the proposed algorithm, with respect to the traditional gradient one, are decreased to approximately 1/ c, where “c” denotes the Schein rank of the fuzzy relation involved. A dual decomposition problem of max–min type is also formulated and a similar fast method is presented. Both methods are applied to image compression/decompression processing. [ABSTRACT FROM AUTHOR]

The biofilm of Pseudomonas aeruginosa could be removed by Varidase (streptodornase) that was used as defibrinating drug. After cultivating the biofilm on a silicone chip in a modified alginate-producing medium in vitro, it was treated with Varidase or DNase I. In both treatments, the biofilm was removed depending on the concentration of the reagents. Varidase was apparently effective under the condition that the biofilm was exposed to more than 625 U/ml (a quarter of the concentration of the medical use) for 3 h, twice, at 37°C. The result of this experiment indicates that (a) the DNases, DNase I and Varidase, were effective in destroying the biofilm of P. aeruginosa in vitro, and (b) in a clinical field, Varidase could be useful for P. aeruginosa focal infection, such as urinary tract infection, by removing the biofilm.Copyright © 2003 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

DC electrical conductivity of vanadium–tellurite films both as-deposited by vacuum deposition and annealed at 773 K for 3 h after deposition are investigated in the temperature range of 323–473 K. All as-deposited films (250–350 nm thickness) show an amorphous structure; the annealed films show some crystalline peaks of TeO2. The conductivity of the as-deposited films at 373 K varies from 1.07 × 10–7 to 3.73 × 10–15 Scm–1. With annealing the conductivity increases by a factor of 10 to 103 due to the presence of some nanocrystals of TeO2 and also increases with an increase of the V2O5 content. The temperature dependence of the conductivity of both as-deposited and annealed films obeys a non-adiabatic small polaron hopping conduction mechanism. Seebeck coefficient measurements indicate all the films to be n-type semiconductors. From absorption edge analysis it is revealed that the optical band gap energy for the films is 2.96 eV and 3.11 eV for as-deposited films. Urbach tail analysis gives the width of localized states as 0.272 eV and 0.392 eV for two as-deposited films. [ABSTRACT FROM AUTHOR]

The grain boundary diffusion (GBD) process is an effective process for enhancing the coercivity of Nd-Fe-B sintered magnets. When the GBD process is applied to a thick magnet, the magnet exhibits a coercivity distribution. Partial coercivity at the centre is the same as that of the original magnet, but the partial coercivity increases on going towards the magnet surface. In this paper, the effects of conditions of the GBD process on the characteristics of coercivity distributions were investigated. Surface coercivities increase with increasing amount of coatings, while diffusion depths are almost the same. The diffusion treatment temperature varied from 800 to 900 degC, and does not affect the coercivity distributions. A long-time diffusion treatment is effective in enhancing the inner coercivities, but a very long treatment causes a significant reduction in surface coercivity. [ABSTRACT FROM AUTHOR]